Some people have story´s they want people to hear or important events to announce. Students also may want to be authors or reporters. So, This would be good practice for them like publishing their story or interviewing others for a story. I think it´s only fair to have school newspapers because there may be a lot of important information.
You should censor a kids newspaper let me tell you why. In the real world they aren't going to let them publish whatever you want it and expect it to be successful. There should be a teacher at the top of the newspaper chain who constantly rejects student newspapers from being published because thats exactly how real life is like